Inertia responsive shock absorber



May 18, 1954 G. cAMPr-:AU

INERTIA RESPONSIVE SHOCK ABSORBER Filed Feb. 25, 1952 Il/IIIIIII; 'IIIA,I

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Patented May 18, 1954 UNITED STATES PATENT GFFICE INERTIA RESPONSIVESHOCK ABSORBER Georges Campeau, Montreal, Quebec, Canada ApplicationFebruary 25, 1952, Serial No. 273,228

(Cl. 18S-88) Claims.

This invention relates to new and useful improvements to automotive orother vehicular shock absorbers, and more particularly, pertains toshock absorbers of the piston-operated, fluiddisplacing type.

The primary object of my invention is to proy vide a novel vehicularshock absorber capable or" arresting rebounding action of a vehicle uponits springs.

Another object is to provide a vehicular shock absorber with a novel,rotary inertia, oil-flow check valve designed to regulate the rate andamount of displacement of the cushioning liquid.

Another object of my invention is to provide an improved shock absorbercapable of permitting a small degree of vertical movement of the axlerelative 'to the body of a vehicle before any cushioning liquid isdisplaced within the absorber.

A further object is to provide a novel simply constructed and easilyassembled vehicular shock absorber wherein all points of division arestrategically located, facilitating assembly, disassembly, and anymachining required within.

A still further object of my invention is to provide a novel means foradjusting the checking tension of the oil-iioW check valve.

Other objects and features of my invention will become more apparentupon reference to the accompanying drawing wherein:

Fig. 1 is a perspective view of my improved shock absorber.

Fig. 2 is a cross-sectional view taken substantially along line 2-2 ofFig. 1.

Fig. 3 is a cross-sectional view taken along line 3-3 of Fig. 2.

Fig. 4 is a fragmentary view of the upper rear portion of my shockabsorber, and showing an exploded View of the rock arm and its componentparts, the rock arm being removed from the shock absorber housing forsake of clarity.

Fig. 5 is a perspective view of the rotary inertia check valve takenapproximately along line 5-5 of Fig. 3.

Fig. 6 is a cross-sectional view taken along line Ei-Ei of Fig. 5.

Fig. 7 is a sectional View similar to Fig. 6 except that the outercasing sleeve is revolved to close the alignment of the exhaust ports.

Referring more particularly to the drawing, 5 indicates generally myshock absorber, which comprises a lower cylinder 6 and an upper, fanshaped housing 1. Projecting outwardly from said housing 1 are flanges 8having holes 9 through which bolts (not shown) secure said shockabsorber to an automobile or like vehicular body. Upper housing 1 issecured to lower cylinder E by means of bolts l0 passed through holes ilin a ange I2 of lower cylinder and being threadedly received in recessesI3 of a co-operating flange ld of upper housing 1. A gasket Ilia ofsuitable material prevents leakage or cushioning :duid introduced intothe shock absorber through an opening l5 in an inclined sidewall i5 ofupper housing 1 (see Fig. 2). A plug l1 threadedly closes opening I5.

A reciprocating piston i8 divides cylinder 6 into a lower chamber '29and an upper chamber 2l. An integrally formed, wall 22 defines the lowerextremity of lower chamber 2li, while the opposing, upper end ofcylinder 6 is open to permit passage therethrough of a piston rod 23. Itwill be noted that cylinder has its open end secured to housing l sothat the integrally formed end wail 22 of the cylinder is remote fromthe connection to the housing. Piston I3 is axially arranged in thecylinder so that its compression stroke is directed towards theintegrally formed end wall 22. Thus it Will be seen that the compressionside of the cylinder, that is, chamber 2i! is of one piece construction.This has considerable advantage over the type of cylinder in which thecompression side is fitted with a removable cap. With applicantsarrangement there is no possibility of leakage in the area of thecylinder where the forces of compression are the greatest.

A split collar 24, forming the lower end or" piston rod 23 rotatablyencases a central portion 25 of a pin 2e journalled in openings 2L-2l ofpiston i8. To prevent any lateral displacement of piston rod 23 upon pin2E, said central portion '25 is of a slightly smaller diameter than thatof pin 26. To permit assembly or dis-asn sembly of rod 23 upon or frompin central porn tion 25, the clamping eiect of the split collar 255 isadjustable by lock nut 28.

At the opposite end of piston rod 23, a yoke 29 is detachably secured toone end of a rock arm 3l] by a pin 3l. Pin 3l is removable only Jforassembly and dis-assembly and is of a fit snug enough tc permitretainanee, yet loose enough to allow free movement of the enjoined rockarm and piston rod.

The opposite end of rock arm 3B, is circular, as indicated at 32, and isreceived in a well 33. One side surface 34 of said circular portion 32abuts in face-to-face relation against wall 35 of receiving well 33. Thecircular portion 32 of rock arm 30 is provided with a trunnion 36 whichis received in a bearing well 31 in wall 35. The opposite surface 38 ofcircular portion 32 is provided with a trunnion 39. The circular portion32 of rock arm 3D is retained in well 33 by a plug 4I threadedlyreceived in the well about trunnion 39. A ring-type bearing 4D is ttedaround trunnion 38 between circular portion 32 and plug 4l. Plug lll isprovided with tool-engaging recesses 42 to permit installation andremoval. Through the openingn resulting from removalio'fplugMzandbearingbfinsertlon or removal of rock'arm 3U is facilitated, as shown toadvantage in Fig. 4 of the accompanying drawings. The outward end oftrunnion 39, is tapered'andfsquaredito receive a correspondinglyapertured arm 43. Trunnion 39 is provided withatlireaieifextension 44which receives a lock nut -(notishown) for retaining arm 43. Theopposite end of arm 43 carries a ball 44a which is received in"a'-corresponding ball socket llocated in one end 46 of a 'push rodfll.Tlieballfand fsocket are lubricated lby 'means of va grease fitting M48.This method oflinkage betweenfarin-AS Vandpu'sh rod 4'! is preferable,although replaceable by `any other suitable connection. yThelpushvrodfl'a 'is connected a't its opposite=end 'tothefaxlebf-:a 4vehicle inanysuitable'ni'anner (not-shown).

Vertical `'movement ofa vehicular'axle rotates arm`43 through: pushrodffil'l,zandrrotation offarm 43, 'by its securedf linkage to -rock armf3l via trunnion 39 and circularrportion232,;rotatesrock arin 30 eitherto I aposition 39a .or vfiile, 'depending on 'whether 'the axle `islraised .or lowered. AnyI displacement fv roeki arm 3@ from: itsfnorm'alcentral position` actuates piston i8 in a recipro eating action'withincylinder S. SmallIin'equalities in road surfaceitendtorotatela'rmlSilonly a few'degreeso angular-magnitude. Since Ath'e are traveloffro'l-'arm 232i, rotated rheseiew 'degrees, l is in fa lateral'direction, '-veryV little longitudina-l --inov'einerit lis @exertedlup'on piston i. `rFliese inequalities eiect Tino .consequential.'rebound -of the alito -lb'ody nponfthei's'prings, norfdotheysubstantially displace anloil-check valvel, hereinafter describedWith'fthe valve l5? -undisturbediafreedemfoffluid lowlisrn intainedresulting infree 'inovsiriani'.I of.ll piston l l S .hout interferingwith-'th'e lvehiele springlr'esiliency.

If,'-lioweverfahlarge `eavitylor bum-p isf-"struck, raisingIorlowerinig'tlie vehicleaxlegreatly,inek arm 535 is rotatedto position33m or 3612, pulling piston i8 approximately to position {Sofas-shown indottedlinesin Fig.2. WhenpistonFFliso moved, displacement of lluidcontained in v fanshaped housing l and in chamber- I .ofcylinde'r iforces open `a normally-closed spring-'closed valve 48a seated in thehead surface of pistoni I8. This fluid passes through exhaust ports14e-circumferentially spaced around vvalve Estemll lof valve 48a and iscontained inllowerehamber-' of cylinder- S.

When the axle is returning'- to its normal .position, rock arm 30,throughits linkagesfreverses its s'wingand thus extends pistoniV l 3toits original lowered position. In 'so returning, valve 48a closes andthe l'iquidi-inlower oonipartment is forcedv through exhaust-porti 5i'located in? the side walls of cylinder. fExhaustport-Sl opens into oneend of a nuid passagefZls'ituated'in a thickened portionff'ofthesi'de*wallfflower cylinder ll-.

At the opposite end' of passage 52 '-afvertical'ly extending fluidlpassage tube54f'hasnneend threadedly received inia'"c`orrespondingrecessS in the outer Aen'df"thickenedwall53. A lock nut 56 secures tube54 within recess 55 against rotation. The free end of tube 54 is bent atright-angles to provide a horizontal extension 54a.

Fitted over the fluid passage tube extension 54a is a weighted,spring-counterbalanced, rotary valve 5l'. This valve 5l is co-axial withtube extension 54a and comprises generally a sleeve 5t, arm 53, andweight 60. Spaced through said i-sleevei58fis arow of luidrexhaushports6| cor- `responding with "like ports 62 in fluid tube 54. A closed endwall 33 of tube extension 54a per- 'mits fluid passage only through saidports 6|, f62. hroughendiwall 63 a pin 64 is passed and permits only aspecified degree of revolution of theivalvefi'l'cabouttube extension 54aby butting Iagainst:shoulders65 of valve arm 59.

As heretofore mentioned, when a bump or cavi-ty'is'struck by thevehicle, the vehicle axle either' rises or drops. The vehicle body isthus forcibly and rapidly :raised .(orllowered) -tcarrying theVattached'sho'cktabsorberhcusing with it. When `said f shock*absorberfhousing i's displaced, the inei-tiafof :valve ."causes: it to:lag: behind, .thuszre- Volving about tube extension 54a I"and :therebyclosing exhaustportstl as .fshowninifig .7. A 'counter-balancing spring66E returns the: displaced 4"valve toitsnorm'aLiopen-portpositionand'maintains it in said position until again shockdisplaced.This-Tcounterbalancingieects aV desired, retarded, gradual'openingof the.exhaust ports 6 i .62. By 'this'.retarded:openinggthese ports permitonlyl'a liinite'dow of 'fiui'dfrom"thezcompression chamber-12 '-totheseco'n'dary chamber .above the piston 158. .fBy Vconsiricting .thisfluid `flow the returnof ftheiax-le Lto its .normal position isretarded,Lfresultinglalsolin 'a gradual returnof the vehiclebodylitoitslnorrnal position through the medium of the shock absorber.

*Spring JSS-'is andoored:v at: one end to tube extension Willa, fsaidend "of 'spring f66 lextending into La transverse `opening `267 -in'..the thickened por-tion of fend wall 33. -The intermediate por*tion'o'f spring-263 'encirclesth'e tube extension 54a and1itsfree''endis-selectively receivable in one of#apluralityl'offrecesses i168.Recesses 68 are radially arranged with respect to the axis o'f tubeextensionff'a. V'Adjustability: off the #valve spring tension -is'e'iected'bydselectiveinsertion of said free end of spring (-26L in'another of therecesses 63.

A``If Aspring 'tension were too weak, the rotary valve would notcentralize itself, leavinglthe exhaust ports losedand'ca-u'sing theshock absorber to be inoperative. SHowever,'if the tension were toogreat, the -exhaust ports would open too quickly causing too rapid nowor iiuid `from one cha-mberlintofanother andthereby resulting in thepistonextendin'gwthoutresistance, permitting the'vehicle'bo'dyto reboundupon its springs. These 'defects may beovercoine by said selectiveadjustment'of f' the lfree end' of spring* G6 to increase ordecrease thespring tension.

It should be understoodthat'fwhile'thisis a preferred embodiment of myinvention, other modificationsmaybe resortedto within' the scope andspirit of the appended claims.

"l What EIv claim: is:

1. A` shockabsorber for vehicles, comprising a fluid containing'housingrigidly connectable to a -vehicle body and'providedwith lan opening, acylinder 'having anopen :endsecured to said 'housing and reglsteringwith`saidl housing opening 'whereby the interior'of' the'cylinder is placedin communication' withthe interior of the housing, a'pstonaxia'llymovable vwithin `said cylinder, means for operably connecting saidpiston to a relatively movable part of said vehicle, said pistondividing said cylinder into a primary chamber at the side of the pistonremote from said housing and a second chamber at the other side of thepiston in direct communication with said housing, said piston beingprovided with a iiuid passage between said primary and second chamber, avalve normally closing said passage through the piston and operable topermit iiuid ilow between the chambers when the piston is retractedtoward said housing, a second fluid passage from said primary chamber tosaid housing, said second fluid passage comprising, in part, acylindrical tube closed at one end and having radially extending portsadjacent its closed end, a weighted, counter-balanced, rotary inertiavalve adapted to osciilate about the axis of said cylindrical tube andhaving exhaust ports normally aligned with said radially extending portsin said tube, said valve being rotatable by forces of inertia to disruptthe alignment of said exhaust ports, and means operable for returningsaid valve to open exhaust port alignment.

2. A device as set forth in claim 1, in which said means for connectingsaid piston to said relatively movable part comprises an oscillatableshaft connected at one end to the said relatively movable part and atoggle linking said shaft to 30 2,017,963

said piston for axial movement of said piston in response to oscillationof said shaft.

3. A device as set forth in claim 1, in which said means for returningsaid inertia valve comprises a counter-balancing spring secured at oneend to said cylindrical tube and at the other end to said valve.

4. A device as set forth in claim 3, including means carried by saidinertia valve for selective connection of the said other end of saidspring for adjustment of the tension of said counterbalancing spring.

5. A device as set forth in claim 3, including means for adjusting thetension of said counterbalancing spring which comprises a plurality ofcircumferentially spaced apertures at the remote end of said valve intoone of which the free end of said spring is selectively secured,adjustability being eected by repositioning said spring end into otherof the spaced apertures.

References Cited in the le of this patent UNITED STATES PATENTS NumberName Date Re. 11,767 Lash Aug. 29, 1899 1,281,079 Sears Oct. 8, 19181,515,863 Kirby Nov. 18, 1924 1,818,140 Lang Aug. 11, 1931 Griswold Oct.22, 1935

